Devoutly loyal to her master, Grayven, Sinthia accompanied the powerful despot on a murderous rampage across the galaxy.  She assisted him in decimating populated worlds as well as nineteen honored members of the Darkstars.  Several years ago, Grayven and Sinthia arrived on the planet Rann and fought against the surviving Darkstars, Adam Strange and neophyte Green Lantern Kyle Rayner.  Kyle managed to keep Sinthia on the defensive, but it was actually Darkstar leader John Stewart who ended their threat when he activated a Mega Zeta-Beam which teleported Grayven off the besieged planet.  With no one to lead her, Sinthia fled the scene.  Her current whereabouts and activities are unknown.